Re: Issue with the H2 state machine

On Fri, Jul 21, 2017 at 10:17:44AM +0200, Willy Tarreau wrote:
> I'm not seeing anything explicitly forbidding to send this sequence. I'm
> obviously not interested in doing it, but I found it while trying to use
> the stream state to know what I have to do when getting back to processing
> a stream, and found that each time I adapted my model differently, I broke
> it another way. I'm thinking about adding sub-states to deal with this here,
> but I wanted to check if 1) I'm overlooking something (or am completely
> stupid) and 2) if some implementations sticking strictly to the specified
> state machine could possibly face issues when dealing with such sequences.

Finally I found that "8.1 HTTP Req/Resp Exchange" more or less addresses
it by remining a normal sequence though without being very strict on what
to do when it doesn't match (lack of HEADERS frame not mentionned for
example). I don't have much better to propose for now however.

Also I think I found a typo here in 8.1 :

   An endpoint that receives a HEADERS
   frame without the END_STREAM flag set after receiving a final (non-
   informational) status code MUST treat the corresponding request or
   response as malformed (Section

I think it should use s/END_STREAM/END_HEADERS/ given that DATA frames
are still allowed here. I can file an errata if confirmed.


Received on Friday, 21 July 2017 08:40:05 UTC